Immunotherapy as a treatment for type 1 diabetes mellitus in children and young adults: A comprehensive systematic review and meta-analysis

Abstract

Background and objective: Type 1 diabetes mellitus (T1DM) is characterized by the loss of pancreatic cells, resulting in total insulin insufficiency. According to the Diabetes Control and Complications Trial, T1DM treatment aims to achieve appropriate glycemic control and to prevent and avoid repeated episodes of hypoglycemia. Insulin therapy alone addresses the symptoms of the disease but fails to target the underlying pathophysiology of T1DM in children despite continuous efforts to enhance insulin regimens. Therefore, immunotherapy-based approaches have been considered potential treatments for T1DM in children since they can regulate the autoimmune responses and enhance the children's quality of life by reducing their daily dose intake of insulin.

Methods: In this meta-analysis, we have covered a few immunotherapeutic options based on preclinical and clinical data, namely, Teplizumab, Golimumab, Imatinib, Etanercept, Canakinumab, Ladarixin, Ala-Ala, Anakinra, and Otelixizumab in reliable databases such as Pubmed, Google Scholar, and Cochrane. SPSS was used for statistical analysis. Mean difference (MD) and standard mean difference (SMD) were used to evaluate the outcomes with a 95% confidence interval (CI).

Results: To assess the effect of immunotherapy on the patients' daily dosage of insulin and their HbA1c and C-peptide levels, data from twelve trials were combined and synthesized. Because of the high levels of heterogeneity in the selected studies, a random-effects model was used for analysis. The combined data showed that patients receiving immunotherapy had higher C-peptide levels (Mean Difference (MD) = 1.51; 95% Confidence Interval (CI): [-2.56, 5.58]); however, this difference was not statistically significant (p = 0.42). On the other hand, patients in the immunotherapy group had significantly decreased HbA1c levels (MD = -0.63; 95% CI: [-1.18, -0.07]; p = 0.03), indicating that immunotherapy had a positive impact on glycemic management. Additionally, patients receiving immunotherapy exhibited a drop in their daily insulin dosage (MD = -1.15; 95% CI: [-2.59, 0.28]); however, this drop failed to achieve statistical significance (p = 0.10), thus indicating the need for additional research.

Conclusion: This meta-analysis aimed to assess the effectiveness of immunotherapy in treating T1DM by examining its effects on the patients' required dose of insulin, C-peptide, and HbA1c levels. While some studies failed to show desired results, the overall effect was an increase in C-peptide levels and a decrease in HbA1c levels. However, the study did not achieve statistical significance for insulin dosing. The main study's strength is its focus on randomized clinical trials which is considered among the highest levels of epidemiological evidence. Therefore, further research is required to minimize the gaps and to explore immunotherapy-based drugs as potential treatments for T1DM.

Fig. 1. PRISMA flowchart of the included studies.

Fig 2. Traffic-light plot.

Display of the risk of bias in the included studies based on Cochrane’s RoB 2.0 tool.

Fig 3. Forest plot of Mean difference of C-peptide levels in patients with Immunotherapy compared to the control or Placebo group.

The size of the blue box indicates the study weight. The red diamond indicates the value for the total estimates.

Fig 4. Forest plot of Mean difference of HbA1c levels in patients with Immunotherapy compared to Control or Placebo Group.

The size of the blue box indicates the study weight. The red diamond indicates the value for the total estimates.

Fig 5. Forest plot of Mean difference of Insulin dose requirements in patients with Immunotherapy compared to Control or Placebo Group.

The size of the blue box indicates the study weight. The red diamond indicates the value for the total estimates.